Maybe, but that's not the point. Using both resistor-type plugs and caps can seriously bugger up some aftermarket ignition systems. Seems nobody wants to RTFM anymore. Maybe the modern vehicle electrical systems that seem to produce more current than the power station down the road can cope with resistors in both components. Ask NGK what they're doing for our old bangers, which do not belong to the category "comply to current legislation".
The precious metals are not about conduction, it's mostly about wear. Healthy ignition systems of any type should work quite satisfactorily with run-of-the-mill copper core plugs, they generally generate more than enough oomph for a nice fat spark at the plug. Tired, old, magneto systems with points could well benefit from the superior conductivity of silver core plugs. Iridium plugs generally have a 100000km change interval in modern engines, something not even silver or gold-palladium plugs could achieve, mine all reached the end of their useful life around the 40000km mark.
Champion N2G and N3G gold-palladium plugs are still available here and there.
Although NGK B8ES and Champion N3C pop up next to another on comparison charts world-wide, they are not the same. Much the same with NGK 9 and N2. Close... but no cigar. The NGK 8s generally require rejetting from factory specs because they run a fair bit hotter, which is then falsley blamed on "modern fuels". With the 9s, it's the other way round, they are considerably colder than the Champs. Imho, a stock Laverda will run happily on modern fuels with factory spec jetting and correct plugs, which don't even need to be Champions!
Never seen anything about NGK products that would make them "unique and superior". Only thing going for them is that there's a rack of them in every second corner-shop...
piet